Anthraquinone dyes and process of making them.



; shades' I have now discovered thatthese- HENRY ISL'ER, 0F MANNHEIM, GERMANY, ASSIGNOR T0 BAJDISCHE ANILIN dz SODA FABRIK, 0F LUDWIGSHAJEEN-ON-THE-BHINE, GERMANY, A CORPORATION.

THRAQUINONE JDYES AND PROCESS 01E MAKING THEM.

No Drawing.

In the specification of application for- U. S. Patent #1,093,427 is described the production of compounds by treating dibenzanthrone which possesses a constitution corresponding to the formula with an oxidizing agent, for instance mangane'se dioxid and sulfuric' acid, either withor without subsequent treatment witha reducing agent, for instance sodium sulfid, and it is there stated that the 'said compounds dye cotton from a hydrosulfite vat olive-green compounds can be converted into new coloring matters lay-heating them, either alone or preferably in the presence of a solvent or suspension agent or. of a suitable condensing agent. The new coloring matters dye valuable green shades from a hydrosulfite vat and possess excellent covering power, brilliance of shade, fastness against the action of soap, and, compared with the initial prod- .ucts, very good fastness agamst the action of chlorin; Y

My new colorin matters consist, when dry, of green pow ers, are insoluble in jdilute acids andalkalis, are very dificultly Specification of Letters Patent.

Patented Dec. l2, idle.

' Application filed February a, 1913. Serial No. 74d,175.

soluble in the organic solvents of high boiling point, but are soluble in alkaline hydrosulfite yielding blue vats.

The following example will serve to illustrate further the nature of my invention, which, however, isnot limited to this example. The parts are by weight. Introduce 10 parts of the oxidation product obtained according to either of the examples of the said Patent #1,093,427 into 100 .parts of para-toluidin, add 5 parts of dry anhydrous boric acid, and heat either at 160" C. or at boiling point, until a test portion shows that no unaltered initial material is present. Then remove the para-toluidin, for instance by means of alcohol or' with dilute hydrochloric .acid. The product can then be dissolved in alkaline-hydrosulfite solution and precipitated again bypassing air throughthe violet-blue vat obtained, whereupon the coloring matter separates out in green flakes. It is soluble in concentrated sulfuric acid with a bluish red color and is insoluble in other condensing agent can be employed;

Similar or identical products can be obtained by treating, in a similar manner, the reduc-- tion products obtainable according to, Example 3 of the saidlPatent No. 1,093,427.

Now what I claim is 1. The process of producing coloring inatters of the anthraquinone series by heating an'oxidation product of dibenzanthrone.

2. The process of producing coloring mattersfof the anthraquinoneseries by heating an oxidation roduct of dibenzanthrone 1n l para-toluidin and boric acid,

the-presence o gt. As new articles of manufacture the col- 0 whic can be obtained-by heating an oxidation product of dihenzanthrone WhlCh new coloring mars consist, when of green powders are insoluble in dilute acids and matters of the anthraquinone series organic solvents of h h boilin point, but

In testimony whereof I have hereunto set my hand in the presence of two silbscribing are soluble in alkaline hydrosu te yielding wltnesses.

blue vats which dye cotton brilliant olivegreen shades of excellent fastness against the action of soap, and very good 'fastness against the action of chlorin. 7

MAX HENRY ISLER. Witnesses J. ALEo. LLOYD, JOSEPH P EIFFER. i 

